Maryland state, Sen. Edward J. Mason (R-Allegany) said he didn't think he should make a speech on the bill to raise the drinking age from 18 to 21, since he recently obtained a liquor license for his restaurant in Cumberland. He spoke anyway, urging defeat of the bill.

Sen. Thomas V. Mike Miller (D-Prince George's), whose father owns a large liquor store in Clinton, and Sen. Tommic Broadwater Jr. (D.-Prince George's) who has an interest in a Prince George's County restaurant with a liquor license, also spoke against the bill.

Over in the House of Delegates, Del. Robert A. Jacques (D.-Montgomery) said he didn't think he should vote on a bill that would affect gas stations, since he has a Rockville station as a legal client. He didn't vote, and urged other attorney-delegates with ties to the oil industry to exercise the same restraint.

The House was still in the midst of a controversy over a bill that would, benefit insurance agents - a measure introduced by three delegates who happen to be insurance agents.

In the span of a single day, members of the Maryland General Assembly thus demonstrated responses ranging from unusually fastidious to lackadaisical in handling the potential conflicts of interest that daily confront part-time legislators here.

By a vote of 27 to 17, the Senate approved the proposal to gradually reestablished 21 as the minimum legal age for purchasing beer and light wine, conceding in the process that it had made a mistake when it lowered the age to 18 in 1974.

The bill now goes to the House, where, according to Speaker John Hanson Briscoe, "It'll have tough going and could very well fail . . . I see no great mover over here to go back to 21."

"The Senate has to realize very simply that when they lowered the drinking age to 18 they made a mistake," said Sen. Jerome F. Connell (D-Anne Arundel), the sponsor of the bill. "If you don't beleive it, start checking some of your schools . . . The Young people have not shown that they can exercise the responsibility that attaches to drinking at that age."

The bill on which Jacques refrained from voting was sponsored by Del. Gerald Devlin (D-Prince George's). It was defeated by a vote of 81 to 35 after Del. Charles E. Smith (D-Frederick) said that "what began as consumer protection will be a consumer nightmare."

Devlin wanted to require service stations that now display huge signs advertising their lowest price gasoline to be required to displace prices of all their grades of gasoline. He said some stations advertise regular gasoline at 55.9 cents a gallon, but sell unleaded for 10 cents higher, although the customers don't know that until they have parked at the pump.

Smith agrued that instead of forcing stations to display signs with all prices, they would post none. Del. Steven V. Skiar (D-Baltimore) agreed, saying the bill would lead to "a conspiracy of silence because station owners would refuse to post six or eight different price signs.

Jacques said he didn't think his gas station law client even knew about the bill, much less cared about it, but added that it is important to actively avoid the appearence of conflicts.

He involved rule 19 of the House, which says "A member may not vote on any question in the result of which he has an immediate personal or financial interest."

The Rockville lawyer said it is bad enough to vote on such legislation, but "it's even worse to sponsor it," noting that "insurance agents are sponsoring bills to promote insurance agents."

It was an apparent reference to the proposal sponsored by bels. Irwin F. Hoffman (D. Washington), Francis J. Santangelo Dr. (D. Prince George's) and Isaiah Dixon Jr. (D. Baltimore) that would prohibit newly formed banks from selling insurance.

The proposal, which was delayed today for consideration Friday, has been criticized on the House floor by Del. Lorraine M. Sheehan (D. Prince George's) not only because its sponsors are all insurance agents, but because she said it would descriminate against women and blacks, two group actively attempting to start new banks in the state.

The House was in such a nonconforming mood today that Majority Leader John S. Arnick (D. Baltimore) whispered to reporters, "I'm not sure I could get a quorum call approved."

The House rejected a second bill, by a vote of 52 to 70, that would have required the State Board of Education to establish regional centers for teachers to take in-service training.

Del. Craig Knoll (D. Prince George's), a former school teacher, denounced the idea as "just another agency" that could do little more than conduct "grandiose staff meetings' for teachers.

In other action, a well-organized presentation to the Senate Economic Affairs Committee by a group of citizen activites seeking a mechanism to control spiraling utility bills, was countered by testimony from the League of Women Voters, a usual ally of consumer bills.

The Maryland Action Committee spent over a year, and raised more than $400,000 in voluntary contributions to push for creation of a Citizens' Utility Board, a utility-customer funded organization that would argue the cause of utility users before the state Public Service Commission.

After a group of citizens - including Dominic Fornaro, head of Maryland's umbrella labor organization - testified in favor of the proposal, League president Dale Balfour critized the bill line, arguing that the proposed board would be duplicative, discriminatory, perhaps unconstituional, and might become a springboard for persons who wished to run for office.