Baltimore's city solicitor defended Friday the purchase of high-tech phones and other equipment by MayorStephanie Rawlings-Blake's administration — an expense that has been questioned by another top City Hall official.

George A. Nilson said the purchase of video phones and other equipment "was neither out of the ordinary, nor in violation of law." The purchase was made under a contract for computer equipment, which Nilson argued was allowed because the phones could be considered computer hardware. The mayor requested the opinion.

The letter comes as two of the city's highest-ranking elected officials — Rawlings-Blake and City Comptroller Joan M. Pratt — continued to square off over control of the city's phone system. The comptroller has accused the Mayor's Office of Information Technology of trying to circumvent purchasing rules by buying phone supplies under the existing computer equipment contract with Rockville-based Digicon Corp.

Nilson, who is appointed by the mayor, said staff members in the information technology office did not violate purchasing protocols. He also said the city's charter does not grant the comptroller sole power over the phone system.

But Pratt dismissed Nilson's letter and maintained that the existing contract did not provide the technology office with the authority to purchase phone-related equipment from Digicon. Pratt said she was considering hiring her own lawyer to review the contracts and purchases.

Pratt contends that the technology office bought more than $650,000 in phone-related equipment, though Nilson contends that $55,000 was spent on phone supplies from Digicon.

"I think they're just trying to flood the public and me with a lot of legal information, but the bottom line is they couldn't purchase telephones" under the contract, Pratt said.

Pratt has accused the mayor's technology office of trying to cobble together an Internet-based phone system with equipment from Digicon at the same time she was conducting a formal process to solicit bids for the new phone system. She has also said that having more than two dozen Digicon contractual employees working in the technology office raises questions about the propriety of the purchase.

Baltimore Inspector General David N. McClintock has launched a preliminary investigation into the purchase of phone equipment.

Pratt and Rawlings-Blake have been sparring publicly for more than a week over who should lead the conversion to "voice over Internet protocol" or "VoIP" phones throughout city government.

The comptroller's office has supervised the city's telephone service since the 1940s, but the mayor believes her technology office is best equipped to supervise the switch to Internet-based phones.

Rawlings-Blake asked earlier this month to defer for three weeks a Board of Estimates vote on a $7.5 million contract with IBM to provide city offices with the phones. Pratt's office had negotiated that contract, in collaboration with the mayor's technology office, over several months. Both officials are members of the spending board.

Rawlings-Blake says that her staffers bought 80 VoIP phones, including some devices with video touch screens, and related equipment, as part of a pilot program to test if they were compatible with the city's infrastructure.

The city has had a blanket "requirements contract" with Digicon since 2006, which allows it to make up to $3.4 million in computer equipment purchases without soliciting formal bids for each one. Digicon officials have not responded to requests for comment.

Such contracts "have been used routinely by the City and its Bureau of Purchases, and approved by the Board of Estimates, for decades," Nilson wrote in his letter.

"These competitively bid contracts, also used by other governments around the country, provide for the purchase of specified types of goods and/or services 'as needed' over a period of time and up to an estimated total amount, as opposed to the 'purchase' of a specific public work or finite quantity of the items sought," he wrote.

Nilson noted that Digicon won its city contract, and subsequent renewals, through a competitive bidding process. Therefore, there was no need for the city to seek bids for items covered by the Digicon contract, "unless it was determined that the City would get a significant savings" by doing so, Nilson wrote.

Nilson also argued that the city might seek bids for purchases under such contracts if the cost represented a significant portion of the overall contract value. The $55,000 in phone related supplies, including $21,000 for VoIP phones, represents less than 2 percent of the total contract value — a relatively small percentage that didn't warrant bidding, Nilson wrote.

But Pratt, who generally maintains a low profile, has continued to question the administration's purchases — and the dollar amount.

In particular, she points to documents prepared by the mayor's technology office that indicate it purchased 124 pieces of equipment at a cost of $441,450 to support the changeover to the VoIP phones.