Leonard S. Blondes, a former Montgomery County state legislator, has been convicted of illegally spending $10,000 entrusted to him in a real estate deal.

Blondes, 48, a lawyer who served in the House of Delegates from 1963 to 1970 and once served as cochairman of the Montgomery County legislative delegation, could be sentenced to up to 10 years in prison and fined $5,000.

The conviction Tuesday followed more than six hours of deliberation by a jury in Charles County, where the trial was moved after all Montgomery County judges disqualified themselves from hearing the case.

James Miller, Blones' attorney, said there probably will be an appeal. Blondes declined to comment.

Blondes previously was twice tried, convicted and acquitted on appeal in a bribery case stemming from his legislative duties. In that case, he was accused of "demanding and accepting" $5,000 from Montgomery County bowling alley proprietors in return for influencing legislation.

This week's conviction following a two-day trial stemmed from Blones' acceptance of $10,000 last December from Washington machanic Ernesto Aleotti. The money was part of a deal between Aleotti and Frederick Henderson, another mechanic who was Blondes client, in which Aleotti was to buy the building he rented from Henderson.

According to undisputed testimony, Blondes deposited the money in his general office account and thereafter spent all or most of it on office and personal expenses.

The $10,000, according to testimony, was to be a downpayment on the property purchase but Blondes testified he regarded it as payment of two years' legal fees from Henderson. Henderson testified he made such an oral agreement with Blondes for the money.

It is against the law, Assistant State's Attorney Timothy E. Clarke pointed out, for a lawyer to place into a general office account money earmarked for an independent escrow account. Under cross-examination, Clarke challenged Blondes' assertion that the money was fro Henderson's legal fees.

Blondes, admitted to practice law in Maryland 22 years ago, testified he was not familiar with the state's laws governing escrow accounts. Once Blondes realized that his actions might cause problems, according to testimony, he borrowed $10,000 from another client to set up a separate escrow account.

The separate escrow account remains intact, and Blondes has asked the D.C. Superior Court to decide whether it belongs to Aleotti or Henderson.

Blondes is free under $5,000 bond pending sentencing Jan. 16 by Charles County Circuit Court Judge George W. Bowling on the convictions for misappropriation by a fiduciary and comingling of escrow funds by an attorney.

Blondes also faces trial in Charles County Jan. 23 on five unrelated charges of embezzling $7,500 from another Montgomery County client.