Congress Watch, a Ralph Nader organization, today labeled the first session of the 96th Congress "the Congress that couldn't . . . the most anticonsumer session of the decade."

In releasing its annual voting index, Congress Watch blamed a drop in support for consumer issues by northern Democrats as a major reason for the shift.

The group said the senators who voted for consumer interests on the fewest occasions were Ted Stevens (R-Ariz.) who each supported what it called consumer interests only 12 percent of the time. Sen. Howard H. Baker Jr. (R-Tenn.) had a lower level of support (9 percent), but the study attributed that to his absence from voting while on his presidential camgaign.

In the House, eight members -- four from Texas -- tied for the "worst" voting records, according to the study. Voting proconsumer only 3 percent of the time were James Collins (R-Tex.), Marvin Leath (D-Tex.), Robert Michel (R-Ill.), Ray Roberts (D-Tex.), Bob Wilson (R-Calif.) Larry Winn Jr. (R-Kan.), Joe Wyatt Jr. (D-Tex) and Don Young (R-Alaska). w

The index rates members of the House and Senate on the basis of their 1979 votes on 40 and 35 key votes respectively. The issues at question represented six areas: consumer protection, government reform, energy, environment, tax reform and waste-subsidy.

Sen. William Proxmire (D-Wis.) received the group's highest proconsumer rating in the Senate with an 89 percent score. He was followed by Sens. Paul Sarbanes (D-Md.) and Gary Hart (D-Colo.) with 83 percent and 78 percent respectively.

In the House, Rep. Gerry Studds (D-Mass.) was the top-rated consumer's friend with a 95 percent rating. Four other members -- George Miller (D-Calif.), Andrew Maguire(D-N.J.), Toby Moffett (D-Conn.) and James Shannon (D-Mass.) -- came in just below Studds with scores of 93 percent.

But overall ratings reveal that members of the Senate, on average, voted proconsumer 43 percent of the time last year, down from 46 percent the year before.

The House saw a similar drop in the average member's proconsumer vote from 44 percent in 1978 to 41 percent last year.

The drop in support for consumer legislation has been steady in the House for the past few years, the report noted, with the 1977 House rating at 47 percent.

Northern House Democrats fell "steadily" from 78 percent proconsumer voting records in 1976 to 68 percent in 1977 and 63 percent in 1977 and 63 percent in 1978 and 1979.

"Programmatically, Congress in 1979 has been the Congress that couldn't," said Congress Watch director Mark Green in an introduction to the report. "It couldn't enact a coherent energy program, nuclear power safeguards, public participation programs or anti-inflationary hospital cost controls."

"It couldn't consider on the floor of either chamber trucking deregulation, lobbying reform, the 'Illinois Brick' rule (which would give consumers broader rights to sue for damages), or public financing of congressional elections," he added. "And it wouldn't even discuss a consumer protection agency, labor law reform, class action reform or an Energy Corporation of America (a publicly owned energy company.)"