THE ONLY BRIGHT SPOT in the results of the Massachusetts ballot questions was the passage of the state Equal Rights Amendment. Its approval adds a long overdue clause to the state constitution that bars discrimination on the basis of sex as well as race, religion or national origin. The Massachusetts success of a state ERA reverses a pattern of ERA rejection set last year and has renewed efforts to approve the national ERA.

For the fourth time, Massachusetts voters were given a chance to modernize the state's regressive tax structure by approving a graduated state income tax. The failure of the graduated income tax is ironic because most of those who voted against it would have had their taxes reduced under the plan. The proponents of the graduated tax, if they are to be successful, must mount a broader campaign to clearly inform the voters of the effects of the graduated tax.

The proposal to establish a public power authority to take over the wholesale generation of electricity suffered from the Commonwealth's reputation for administrative incompetence. A very heavy advertising campaign, largely financed by the private utility companies, also contributed to the proposal's defeat. A public power authority would have provided Massachusetts consumers with cheaper electricity and would have instituted more centralized planning for the state's power needs.

A very worthwhile and perhaps life-saving measure that also met defeat on Tuesday was the proposed law banning private ownership of handguns. While only a national ban on handguns will be truly effective in stopping the violence and death that handguns are certainly the instrument, and perhaps the cause of, this law would have been a major step in that direction.

Finally, the proposal to ban non-returnable bottles and cans in an effort to improve the environment and conserve energy through recycling suffered a narrow and bitter defeat. It was in part a victim of a saturation-level advertising campaign that often distorted the aims and implications of the bill, falsely claiming for example, that it would not encourage recycling and would cost the state jobs.

The advocates of the bottle bill should not give up. On Tuesday, similar bills passed in other states, and the slim margin of defeat here shows that it is far from impossible to pass the bill in Massachusetts.